<template>
<div class="app-container">
<h2 style="text-align: center;">发布新课程</h2>
<el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">
<el-step title="填写课程基本信息"/>
<el-step title="创建课程大纲"/>
<el-step title="提交审核"/>
</el-steps>




<el-form label-width="120px">
 <el-form-item label="课程标题">

<el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课：从基础到搭建项目视"></el-input>
 </el-form-item>
 <!-- 所属分类 TODO -->
 <el-form-item label="课程分类">
            <el-select
                v-model="courseInfo.subjectParentId"
                placeholder="一级分类" @change="subjectLevelOneChanged" >

                <el-option
                    v-for="subject in subjectOneList"
                    :key="subject.id"
                    :label="subject.title"
                    :value="subject.id"/>

            </el-select>

            <!-- 二级分类 -->
            <el-select v-model="courseInfo.subjectId" placeholder="二级分类">
                <el-option
                    v-for="subject in subjectTwoList"
                    :key="subject.id"
                    :label="subject.title"
                    :value="subject.id"/>
            </el-select>
        </el-form-item>

 <!-- 课程讲师 TODO -->
<el-form-item label="课程讲师">
        <el-select
            v-model="courseInfo.teacherId"
            placeholder="请选择">

            <el-option
                v-for="teacher in teacherList"
                :key="teacher.id"
                :label="teacher.name"
                :value="teacher.id"/>

        </el-select>
        </el-form-item>


 <el-form-item label="总课时">
            <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder="请填写课程的总课时数"/>
        </el-form-item>

        <!-- 课程简介 TODO -->
        <el-form-item label="课程简介">
                        <tinymce :height="300" v-model="courseInfo.description"/>
        </el-form-item>

        <!-- 课程封面-->
        <el-form-item label="课程封面">

            <el-upload
                :show-file-list="false"
                :on-success="handleAvatarSuccess"
                :before-upload="beforeAvatarUpload"
                :action="BASE_API+'/eduoss/fileoss'"
                class="avatar-uploader">
                <img :src="courseInfo.cover">
            </el-upload>

        </el-form-item>


        <el-form-item label="课程价格">
            <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder="免费课程请设置为0元"/> 元
        </el-form-item>

        <el-form-item>
            <el-button :disabled="saveBtnDisabled" type="primary" @click="saveOrUpdate">保存并下一步</el-button>
        </el-form-item>

</el-form>
  </div>
</template>

<script>
import course from '@/api/teacher/course'

import teacher from '@/api/teacher/teacher'
import subject from '@/api/teacher/subject'

import Tinymce from '@/components/Tinymce' //富文本编辑器组件
export default{
    components: { Tinymce },
    data(){
        return{
                saveBtnDisabled: false,
                courseInfo:{
                    title: '',
                    subjectId: '',//二级分类id
               subjectParentId: '',
                teacherId: '',
                lessonNum: 0,
                description: '',
                cover: '/static/OIP.jpg',
                price: 0
                },
                 BASE_API: process.env.BASE_API, // 接口API地址
                teacherList: [],
                subjectOneList: [],
                subjectTwoList: [],
                courseId: ''    
        }
    },
    created(){
        
        
        if(this.$route.params && this.$route.params.id) { 
             this.courseId=this.$route.params.id
                this.getInfo()
         }else{
                this.getAllTeacher(),
                this.getOneSubject()
         }
},
methods:  {
        getInfo(){
                course.getCouseInfo(this.courseId).then(response=>{
                    this.courseInfo=response.data.courseInfVo
                    
                    //查所有分类
                    subject.getSubject().then(response=>{
                       this.subjectOneList=response.data.list
                       //把一级分类遍历  比较当前courseInfo中一级分类相同的   拿出其中的二级分类
                      for(var i=0;i<this.subjectOneList.length;i++){
                            var subone=this.subjectOneList[i];
                            if(this.courseInfo.subjectParentId==subone.id){
                                this.subjectTwoList=subone.children
                            }
                      }
                    })

                    this.getAllTeacher()
                })
        },

    //上传封面成功的方法
    handleAvatarSuccess(res,file){
        this.cover=res.data.url
    },
    //上传之前
    beforeAvatarUpload(file){
        const isJPG = file.type === 'image/jpeg'
            const isLt2M = file.size / 1024 / 1024 < 2

            if (!isJPG) {
                this.$message.error('上传头像图片只能是 JPG 格式!')
            }
            if (!isLt2M) {
                this.$message.error('上传头像图片大小不能超过 2MB!')
            }
            return isJPG && isLt2M
    },
    subjectLevelOneChanged(value) {
            //value就是一级分类id值
            //遍历所有的分类，包含一级和二级
            for(var i=0;i<this.subjectOneList.length;i++) {
                //每个一级分类
                var oneSubject = this.subjectOneList[i]
                //判断：所有一级分类id 和 点击一级分类id是否一样
                if(value === oneSubject.id) {
                    //从一级分类获取里面所有的二级分类
                    this.subjectTwoList = oneSubject.children
                    //把二级分类id值清空
                    this.courseInfo.subjectId = ''
                }
            }
        },
    getOneSubject(){
        subject.getSubject().then(respose=>{
             this.subjectOneList=respose.data.list
           
        })
    },

    getAllTeacher(){
        teacher.getAllTeacher().then(response=>{
            
               this.teacherList= response.data.stulist
        })

    },
    //添加课程
    addCourse(){
            course.addCourseInf(this.courseInfo).then(response=>{
                    
                     this.$message({
            type: 'success',
            message: '添加成功!'
          });
             this.$router.push({path:'/course/chapter/'+response.data.courseId})
            })
    },
    updateCourse(){
        course.updateCourseInfo(this.courseInfo).then(response=>{
                    
                     this.$message({
            type: 'success',
            message: '修改成功!'
          });
             this.$router.push({path:'/course/chapter/'+this.courseId})
            })

    },
        saveOrUpdate(){
            if(!this.courseInfo.id){
                this.addCourse()
            }else(
                this.updateCourse()
            )
          
        }
}
}

</script>
<style scoped>
.tinymce-container {
line-height: 29px;
}
</style>